1. Technical Field
The present invention relates to a seat cushion airbag apparatus, in which an airbag disposed inside a seat unit of a vehicle seat is inflated by an inflation gas so that a seat face thereof can be raised, thereby preventing a subject to be restrained on the seat unit from being moved forward.
2. Background Art
As techniques for improving pleasant feeling of an occupant seated on a vehicle seat, for example, a ‘vehicle seat air conditioning apparatus’ is known from JP-A-11-048772. The vehicle seat air conditioning apparatus includes an air blowing duct having a blow-out port below a seat cushion of a seat unit, and the conditioning air (a cold air, a warm air, or the like) flowing through the air blowing duct is blown out upward from the blow-out port. The conditioning air is contacted with the occupant through the seat cushion, and thus the occupant can feel a pleasant cold or warm feeling.
Meanwhile, in a vehicle, a submarine phenomenon, in which, when an impact due to a front collision or the like is applied to the vehicle from the front, a waist region of the occupant restrained to the vehicle seat by a seat belt device may be disengaged from a lap belt portion and be moved forward (slid forward), becomes a problem. Accordingly, various measures for preventing the submarine phenomenon have been taken or proposed.
As one of such measures, a seat cushion airbag apparatus applied to a vehicle seat, in which a seat cushion as a seat unit is supported, from a lower side thereof, by a supporting portion of a seat frame, is known. The supporting portion is constituted of spring members (wire frame portions) for elastically supporting the seat cushion from the lower side thereof, engaging hooks, on which the spring members are hooked, and the like.
In the seat cushion airbag apparatus, an airbag having an inflator built therein is arranged between the supporting portion and the seat cushion (see JP-A-2002-079861 and JP-A-2005-306252). In general, the airbag is disposed in a deployed state (un-folded state). Also, the airbag is inflated by an inflation gas blown out from the inflator, thereby raising a seat face of the seat unit. Due to raising of the seat face, a part of the femoral region of the occupant, which is adjacent to a rear side of the knee region, is pressed upward so that the waist region is pressed against the lap belt portion. Thus, the performance of the lap belt portion for restraining the occupant is improved, thereby restricting the waist region from being moved forward (slid forward).
However, when the seat cushion airbag apparatus is applied to a vehicle seat in which the vehicle seat air conditioning apparatus is incorporated, the airbag in the deployed state can be located above the blow-out port, depending on a location of the blow-out port of the air blowing duct. In this case, there is a possibility: that the blow-out port is blocked by the airbag so that the conditioning air is hardly transmitted to the occupant, thereby decreasing pleasant feeling.
The above problem can similarly occur even if subjects to be restrained, which are different from the waist region of the occupant, exist on the seat unit.
Accordingly, the present invention has been made keeping in mind the above problems, and an object thereof is to provide a seat cushion airbag apparatus, in which a subject to be restrained on a seat unit can be prevented from being moved forward, while blowing out of a conditioning air from a blow-out port is not hindered.